ABSTRACT Continued tobacco smoking following a diagnosis of cancer is associated with decreased survival time, increased risk of recurrence, second primary malignancies, increased treatment complications and treatment failure. Despite the adverse health effects of continued smoking, 50% of patients with cancer who smoked prior to diagnosis continue to do so after diagnosis. Unfortunately, tobacco use treatment is not considered a core service at most ofthe National Cancer Institute (NCI) cancer centers, leaving the majority of cancer patients who want to quit with no formal assistance. In addition, there have been few smoking cessation trials for cancer patients and many ofthe trials that have been conducted have lacked biochemical verification of abstinence. There are very few smoking cessation clinical trials that have targeted Hispanic smokers, and we are unaware of any that have targeted Hispanic smokers currently undergoing cancer treatment. A recent NCI Conference on Treating Tobacco Dependence at Cancer Centers (NCl-CTTDCC) highlighted the need for improvement in these treatments, and has called for studies that evaluate methods for integrating cessation treatment into care delivery and sustaining cessation. There is evidence that cancer patients are more nicotine dependent and have more comorbid emotional and mood symptoms than the general population of smokers, suggesting that they may need more intensive forms of treatment than what is available through standard of care approaches. Quitlines have been found to significantly increase abstinence rates compared to brief interventions. While the effectiveness of quitiines in providing cessation support to smokers in the general population is well established, the willingness of cancer patients who are currently undergoing cancer treatment to use quitlines is unknown. In line with the recommendations of the NCl-CTTDCC to evaluate strategies for integrating cessation treatment into cancer care, the current pilot study will assess the feasibility of adding a quitline counseling component to clinical practice guideline-based brief counseling provided by medical staff; and estimate the effect size of the combined brief intervention counseling and quitline (BC+) compared to the brief counseling alone (BC) on abstinence at 3 and 6 month follow-ups. To accomplish these aims, cancer patients undergoing cancer treatment who are current smokers will be randomly assigned to receive brief counseling plus smoking cessation pharmacotherapy delivered in the oncology clinic setting (BC) or the BC intervention plus 7 counseling sessions delivered by the Puerto Rico Quitline (BC+). Smoking outcomes will be assessed at 3 and 6 months post-cessation. Data from this trial will be used to support larger scale clinical trials evaluating quitline delivered smoking cessation treatments for Hispanic cancer patients.